Diverting and sampling gate

ABSTRACT

A gate for diverting and/or sampling the entire flow of particulate material in an upright chute. The gate includes a gate means positioned to extend slidably from an inoperative position in which the gate means spans substantially none of the cross-sectional area of the upright chute means through an opening in a wall of the upright chute to an operative position in which the gate means spans the entire cross-sectional area of the upright chute. Not only is the chute easily constructed and operated, it permits taking a sample with greater confidence in the qualititative and quantitative analysis of the sample.

llited tates Patent 1 Pink et a1.

[451 May 29, 1973 DIVERTING AND SAMPLING GATE Inventors: Werner R. Bink,Fort Saskatchewan, Alberta; George Dempster, Edmonton, Alberta, both ofCanada Assignee: Sherritt Gordon Mines Limited,

Toronto, Ontario, Canada Filed: Oct. 5, 1970 Appl. No.: 77,985

References Cited I UNITED STATES PATENTS 2,550,240 4/1951 Geiger et a1143/31 R X 3,253,470 5/1966 Platzer et al ..73/423 X 1,521,545 12/1924Kistler ..73/423 S 7] ABSTRACT A gate for diverting and/or sampling theentire flow of particulate material in an upright chute. The gateincludes a gate means positioned to extend slidably from an inoperativeposition in which the gate means spans substantially none of thecross-sectional area of the upright chute means through an opening in awall of the upright chute to an operative position in which the gatemeans spans the entire cross-sectional area of the upright chute. Notonly is the chute easily constructed and operated, it permits taking asample with greater confidence in the qualititative and quantitativeanalysis of the sample.

5 Claims, 3 Drawing Figures PATENIEU NW2 9 I973 Agent 1 DIVERTING ANDSAMPLING GATE This invention relates to gates for diverting and/orsampling the flow of material, particularly gates which involvediverting the entire flow of material.

Handling materials flowing through chutes and other conduits oftenrequires sampling the material as it flows through the chute. A numberof devices have already been proposed for sampling material flowingthrough chutes.

U.S. Pat. No. 1,966,712 teaches such a prior art sampler intended forsampling grain. The sampler inserts a tube open at one side into astream of grain flowing inside a larger diameter tube. Only the grainwhich happens to be intercepted by the inserted tube appears in thesample. Since the area of the opening in the tube is substantiallysmaller than the cross-sectional area of the larger diameter tube, anysegregation by grain size would result in a non-representative samplebeing obtained.

US. Pat. No. 2,370,260 also teaches the insertion of a small diametertube open at one side for intercepting a portion of the fine particlesflowing through a larger tube. The particles flow through the smalldiameter tube to a sample container, instead of being retainedtemporarily in the small tube. Again, the sampler does not necessarilyprovide a representative sample.

US. Pat. No. 2,683,373 teaches the swivelling insertion of an open-sidedsmall diameter horizontal tube into a vertical chute containing fallinggrain. The tube opening faces upward inside the chute, the tube beingswivelled or rotated 180 upon withdrawal to face the opening downwardfor automatic emptying. Not only does this sampler intercept only aportion of the material flowing within the chute but it is relativelycomplicated due to the swivelling feature.

U.S. Pat. No. 3,066,539 teaches the insertion of a grooved plunger intoa conduit containing wood pulp flowing under pressure. The pulp incidentupon the groove is deflected along the groove to be deposited outsidethe conduit in a sample container.

The flow of dry, particulate solids flowing through chutes, as in dryingand blending circuits is commonly regulated by a number of two-wayvalves.

In addition to flow regulating, two-way valves are adaptable to flowsampling. When used for flow sampling, conventional two-way valves yieldsamples which are biased by flow segregation, a phenomenon which occursespecially near'the walls of the chute when a distribution of particlesize exists.

, A number of factors contribute to flow segregation, including thesize, specific gravity and shape of the particles of material, the slopeof the chute, the roughness of the interior surfaces of the chute, andthe coefficient of friction betweenthe chute and the individualparticles. The result of flow segregation may be an uneven distributionof particles of the same size throughout a cross-section of the flow.Hence, a sampler which intercepts but a portion of the flow of materialin the chute inherently yields a sample which is not representative ofthe entire range of particle sizes occurring in the flow.

It is an object of this invention to provide a gate which ensures eitherdiverting or sampling the entire flow of dry, particulate matter flowingwithin a chute.

It is a further object of this invention to provide a diverting-samplinggate which is simple in action and construction.

It is a yet further object of this invention to provide a sampling gatewhich will yield a totally representative sample of the material in thechute, regardless of the flow segregation occurring within the chute.

It is additionally an object of this invention to provide a divertinggate which is readily convertible to a sampling gate.

Other objects and advantages of this invention will become obvious tothose skilled in the art.

It has been surprisingly found that it is possible to divert thecomplete flow of material in a chute, for regulation or for obtainingfully representative samples, by using a simple yet completely effectivegate.

The gate is basically a diverting gate which, with the addition of asample pocket or other sample retainer, may be used as a sampling gate.

The diverting gate comprises, in combination, a substantially uprightchute means having at least one wall, a gate means positioned to extendslidably from an inoperative position in which the gate means spanssubstantially none of the cross-sectional area of the upright chutemeans through a first opening in one of said at least one wall of theupright chute means to an operative position in which the gate meansspans the entire cross-sectional area of the upright chute means, secondchute means for receiving diverted material through a second opening inone of said at least one wall of the upright chute means when said gatemeans is in said operative position, said second chute means having atleast one wall, actuating means for extending the gate means across theupright chute means, so that extending the gate means across the entirecross-sectional area of the upright chute means to the operativeposition results in diversion of the entire flow of material from theupright chute means to the second chute means.

The operation and construction of the diverting/sampling gate will bebetter understood when considering attached FIGS. 1, 2 and 3 whichillustrate a preferred embodiment of the diverting/sampling gate. inthese Figures,

FIG. 1 shows a partially cut away perspective view of the preferreddiverting gate according to this invention;

FIG. 2 shows a vertical cross-section of the preferred diverting gate inthe non-diverting position; and

FIG. 3 shows a perspectigve view of a preferred embodiment of thesampling gate according to the invention showing the chutes in dottedoutline.

FIG. 1 shows an upright first chute 10 having a wet angularcross-section and flanged ends. Chute 10 includes inclined gate 12fitted inside chute 10 which is in the operative position, i.e. theposition in which the gate 12 spans the entire cross-sectional area ofupright chute l0. Chute 10 includes funnel l4 upstream from the gate torestrict the cross-sectional area of the flow of material to less thanthe cross-sectional area of the substantially upright chute 10. Thishelps to prevent the particulate matter from being lost between gate 12and the walls of the upright chute 10. The gate includes a seal 16 whichis shown against the wall of upright chute 10 opposite the opening 18through which gate 12 slides. Seal 16 prevents particulate matter fromleaving upright chute 10 when the gate 12 is moved to the inoperativeposition, i.e. the position in which the gate 12 spans substantiallynone of the cross-sectional area of the upright chute 10. Forair-tightness, seal 16 includes a gasket 20 which comprises acircumferential strip of sealing material.

The gate 12 also includes side walls 22 which are mounted on the edgesof the gate 12 to prevent particulate material from being lost betweenthe gate 12 and the walls of the upright chute 10. The upper edges ofthe walls 22, the gate 12 and the lower end of funnel 14 are allparallel. The lower the bottom end of funnel 14 is, the less particulatematerial will be lost between the gate 12 and the walls of upright chute10.

Gate 12 extends into a second chute 24 which receives particulatematerial diverted by gate 12. Within second chute 24 is a fixed rod 26which supports the lower end of gate 12. The other end of gate 12 issupported by rod 28 which passes through the wall of upright chuteopposite opening 18. Rod 28 transmits the motion of pneumatic cylinder30 to the gate 12 via seal 16.

The upright chute 10 has flanges 44, 46 on its upper and lower endsrespectively to permit easy and quick installation and removal of thediverting gate.

FIG. 2 shows the gate 12 in the inoperative position with seal 16 andgasket registering with opening 18.

Rod 28 passes through a removable wall portion 32 which may be removedto permit removing the gate 12 from the diverting gate.

Funnel 14 narrows quickly at its top and extends downward to a bottomedge out parallel to gate 12. The bottom edge of funnel 14 is positionedas low as possible without interfering with the operation of gate 12 orthe flow of particulate material into chute 24.

FIG. 3 shows in dotted outline part of the upright chute 10', the flangeat its lower end, and second chute 24'. In addition to seal 16 and walls22', there is mounted on gate 12 an end wall 34 which stops particulatematerial flowing along gate 12. Taken together, seal 16, side walls 22,gate 12 and end wall 34 form a sample pocket which retains whateverparticulate material is incident on gate 12 when moved to the operativeposition. When the gate is moved to the inoperative position shown inFIG. 3, the sample is removed through the access door 36 in second chute24, both shown in dotted outline.

When in operation, the diverter gate is in the position shown in FIG. 1.The flow of particulate material enters chute 14 which restricts itscross-sectional area to less than that of upright chute 10. Then therestricted flow of particulate material is deflected by gate 12, asshown by arrow 38. The deflected flow travels along gate 12 into secondchute 24 and through chute 24 as shown by arrow 40. When it is no longerdesired to divert the flow to chute 24, the pneumatic cylinder is usedto move gate 12 into the inoperative position shown in FIG. 2. Now theflow passes downwardly through chute 10 in the direction of arrow 42deflected only slightly by rod 28. Seal 16 prevents the escape of anyparticles through opening 18. Pneumatic cylinder 30, which is doubleacting, is used to move the gate 12 back to its operative position whenflow diversion is once again desired.

When the gate 12 is modified as shown in FIG. 3 with walls which form asample pocket, the diverting gate may be used as a sampling gate. Thegate 12 is moved to the operative position by pneumatic cylinder 30 fora fixed period of time. Then gate 12 is moved back to the inoperativeposition by pneumatic cylinder 36 and the flow sample removed throughaccess door 36. Since the sample is completely representative of theparticulate material flowing through chute 10', a quantitative analysisof the sample may be made with confidence.

The sampling gate may not only be used for sampling the composition ofthe material flowing through the substantially upright chute, but mayalso be used to quantitatively determine the rate at which the materialflows through the chute. The period of time during which the sample istaken may be accurately determined and accurately repeated by using atiming means to regulate the amount of time the gate means is operative.Weighing the sample taken during the measured period of time permitscalculating the flow rate in, for example, tons per hour.

Gate 12 is shown in all drawings as being inclined from the horizontal.To encourage the flow of particulate material along it, the angle ofinclination of gate 12 should be greater than the angle of repose of theparticulate material being handled.

Although the Figures all show gate 12 as moving coaxially with chute 24,gate 12 could also be moved in a direction perpendicular to the planeformed by the upright chute 10 and the second chute 24. In thisembodiment, a seal would be mounted at the lower end of andperpendicular to the outer face of one of the walls 22 to register withopening 18 when the gate 12 is removed from chute 10.

Although funnel 14 is shown entirely within chute 10, it may be separatefrom chute 10 and may be open to the air at its upper end.

In an arrangement which requires no funnel, but which performs in amechanically equivalent manner, chute 10 ends just above gate 12 orwalls 22 or seal 16, whichever is higher, and is cut at an oblique anglesimilar to funnel 14. Another chute, which is coaxial with chute 10,flares outwardly to gate 12 from a few feet above it, and encloses gate12, thus permitting gate 12 to be wider than chute 10. Although nofunnel, per se, is required, equivalent operation is obtained.

Although rod 28 is shown attached to seal 16, it could alternatively beattached to gate 12.

It will be understood, of course, that modifications can be made in thepreferred embodiment of the present invention as described hereinabovewithout departing from the scope and purview of the appended claims.

What I claim as new and desire to protect by Letters Patent of theUnited States is:

l. A diverting gate for diverting the vertically downward flow ofparticulate material comprising, in combination, substantially uprightchute means having at least one wall in which is formed an opening, gatemeans inclined from the horizontal at an angle greater than the angle ofrepose of the material flowing through the upright chute and positionedto extend slidably from an inoperative position in which said gate meansis outside said chute and spans none of the crosssectional area of theupright chute means to an operative position in which said gate means iswithin said chute and spans the entire cross-sectional area of theupright chute means and thereby serves to divert the flow of particulatematerial from a vertically downward direction to a direction along thegate means and to said opening, said gate means having at least oneupstanding wall mounted on a lower end thereof across the flow ofmaterial to stop the flow along the gate means, said gate means having awall mounted on an upper end thereof and which, in co-operation withsaid one upstanding wall, forms a sample pocket for diverted material, asubstantially air tight seal on said wall on the upper end of said gatemeans and disposed the second chute means.

2. A diverting gate according to claim 1, wherein the substantiallyupright chute means includes a funnel upstream from the gate means torestrict the crosssectional area of the flow of material to less thanthe cross-sectional area of the substantially upright chute.

3. A diverting gate according to claim 1 including at least one sidewall mounted on an edge of the gate means parallel to the flow ofmaterial to prevent material flowing along the gate means from beinglost between the gate means and the walls of the chute wherein said atleast one side wall is mounted on an edge of the gate means parallel tothe direction of flow.

4. A diverting gate according to claim 1 wherein the substantiallyupright chute means has a rectangular cross-section.

5. A diverting gate according to claim 1 wherein the actuating means isa pneumatic cylinder.

1. A diverting gate for diverting the vertically downward flow ofparticulate material comprising, in combination, substantially uprightchute means having at least one wall in which is formed an opening, gatemeans inclined from the horizontal at an angle greater than the angle ofrepose of the material flowing through the upright chute and positionedto extend slidably from an inoperative position in which said gate meansis outside said chute and spans none of the cross-sectional area of theupright chute means to an operative position in which said gate means iswithin said chute and spans the entire cross-sectional area of theupright chute means and thereby serves to divert the flow of particulatematerial from a vertically downward direction to a direction along thegate means and to said opening, said gate means having at least oneupstanding wall mounted on a lower end thereof across the flow ofmaterial to stop the flow along the gate means, said gate means having awall mounted on an upper end thereof and which, in co-operation withsaid one upstanding wall, forms a sample pocket for diverted material, asubstantially air tight seal on said wall on the upper end of said gatemeans and disposed within the upright chute, said seal registering withthe opening to minimize the loss of material from the chute when thegate means is in said inoperative position, second chute means incommunication with said opening when said gate means is in the operativeposition and receiving diverted material, and actuating means forextending the gate means across the upright chute means to the operativeposition in order to divert the entire flow of material from the uprightchute means to the second chute means.
 2. A diverting gate according toclaim 1, wherein the substantially upright chute means includes a funnelupstream from the gate means to restrict the cross-sectional area of theflow of material to less than the cross-sectional area of thesubstantially upright chute.
 3. A diverting gate according to claim 1including at least one side wall mounted on an edge of the gate meansparallel to the flow of material to prevent material flowing along thegate means from being lost between the gate means and the walls of thechute wherein said at least one side wall is mounted on an edge of thegate means parallel to the direction of flow.
 4. A diverting gateaccording to claim 1 wherein the substantially upright chute means has arectangular cross-section.
 5. A diverting gate according to claim 1wherein the actuating means is a pneumatic cylinder.